The term 'Boy King of Egypt' refers to Tutankhamun, who was an Egyptian pharaoh of the 18th dynasty. He is often referred to as 'King TUT'. His reign lasted from 1332 BC to 1323 BC and he is most famously known for his intact tomb, discovered in 1922 by Howard Carter. The crossword solutions for this term are TUT (3 letters) and AIDA (4 letters). TUT is an abbreviation of Tutankhamun's name, while AIDA is a reference to the opera of the same name, which is based on the story of the Boy King of Egypt.